toshiba_acpi, toshset, and transreflectivity

The new version of toshset (1.73, available at http://www.schwieters.org/toshset ) supports the r500 transreflective screen via the option

toshset -trmode

Usage is simple: to turn the backlight off and use the display in direct sunlight, type

toshset -trmode off

To turn the backlight back on, type

toshset -trmode on

Note that you can still use the display in direct sunlight without turning the backlight off (this works fantastically, btw). The trmode option simple saves you (much) power.

There are some caveats to getting this to work, however:

1. The toshiba kernel module must not be loaded, so remove it from /etc/modules .
2. The character device 181 must be associated with toshiba_acpi kernel module, not the toshiba kernel module. This change can be made in /etc/modprobe.d/aliases .
3. The patch toshiba_acpi-dev_toshiba_test5-linux_2.6.21.patch must be applied. This works fine with the 2.6.24 kernel :
cd /usr/src/linux-2.6.24-2
cd drivers/acpi
patch -p0 < /tmp/toshiba_acpi-dev_toshiba_test5-linux_2.6.21.patch
cd ../..
make modules
make modules_install
4. If the file /etc/modprobe.d/toshiba_acpi.modprobe exists, open it and comment out the line
options toshiba_acpi hotkeys_over_acpi=1

The fingerprint reader supposedly works with libfprint (no Ubuntu package, not bothering).
The SD card reader still cannot read cards (mmc0: error -110 whilst initialising SD card).
Hibernation (aka suspend-to-disk) still doesn't resume, probably because of Ubuntu's swap-device-UUID-changing problem.

One more fun fact: change the Xorg driver from 'i810' to 'intel' :
Driver "intel"
Helps keep X from hanging due to an illegal instruction. Isn't running Linux fun?